Leo says that formatting that SD card is a good idea. Otherwise, a microSD card is about $25 for 8GB.
He's also having difficulty connecting to Wi-Fi with his Galaxy S III. Leo also says that Galaxy S IIIs have more trouble with WiFi these days and he thinks it's due to the phone being "promiscuous" with all the WiFi signals out there to the point it's getting confused. If he can't connect, he should take it back, because there might be a problem with that handset. He could try connecting on the 5Ghz band too.